Image forming apparatus and image forming method
Abstract
An image forming apparatus includes an image bearing member, a charger, and a cleaning member. The charger charges a circumferential surface of the image bearing member to a positive polarity. The cleaning member is pressed against the circumferential surface of the image bearing member and collects a toner remaining on the circumferential surface of the image bearing member. A linear pressure N of the cleaning member on the circumferential surface of the image bearing member is at least 14 N/m and no greater than 40 N/m. A rebound resilience R of the cleaning member at a temperature of 25° C. is at least 38%. The leaner pressure N and the rebound resilience R satisfy mathematical formula (1A). The image bearing member satisfies mathematical formula (1B). R < 13.771 × N 0.4043 ( 1 A ) 0.60 ≦ V ( Q / S ) × ( d / ɛ r · ɛ 0 ) ( 1 B )
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1. An image forming apparatus comprising:
an image bearing member;
a charger configured to charge a circumferential surface of the image bearing member to a positive polarity; and
a cleaning member pressed against the circumferential surface of the image bearing member and configured to collect a toner remaining on the circumferential surface of the image bearing member, wherein
a linear pressure N of the cleaning member on the circumferential surface of the image bearing member is at least 14 N/m and no greater than 40 N/m,
a rebound resilience R of the cleaning member at a temperature of 25° C. is at least 38%,
the leaner pressure N and the rebound resilience R satisfy mathematical formula (1A),
the image bearing member includes a conductive substrate and a single-layer photosensitive layer,
the single-layer photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin, and
the image bearing member satisfies mathematical formula (1B),
R
<
13.771
×
N
0.4043
(
1
A
)
0.60
≦
V
(
Q
/
S
)
×
(
d
/
ɛ
r
·
ɛ
0
)
(
1
B
)
where in mathematical formula (1B),
Q represents a charge amount of the image bearing member,
S represents a charge area of the image bearing member,
d represents a film thickness of the single-layer photosensitive layer,
ε r represents a specific permittivity of the binder resin contained in the single-layer photosensitive layer,
ε 0 represents a vacuum permittivity,
V is a value calculated in accordance with the following expression: V=V 0 −V r ,
V r represents a first potential of the circumferential surface of the image bearing member yet to be charged by the charger, and
V 0 represents a second potential of the circumferential surface of the image bearing member charged by the charger.
2. The image forming apparatus according to claim 1 , wherein
the hole transport material includes a compound represented by general formula (10),
where in mathematical formula (10),
R 13 to R 15 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 4 or an alkoxy group having a carbon number of at least 1 and no greater than 4,
m and n each represent, independently of one another, an integer of at least 1 and no greater than 3,
p and r each represent, independently of one another, 0 or 1, and
q represents an integer of at least 0 and no greater than 2.
3. The image forming apparatus according to claim 1 , wherein
the hole transport material includes a compound represented by chemical formula (HTM-1)
4. The image forming apparatus according to claim 1 , wherein
the binder resin includes a polyarylate resin including a repeating unit represented by general formula (20),
where in general formula (20),
R 20 and R 21 each represent, independently of one another, a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 4,
R 22 and R 23 each represent, independently of one another, a hydrogen atom, a phenyl group, or an alkyl group having a carbon number of at least 1 and no greater than 4,
R 22 and R 23 may be bonded to one another to form a divalent group represented by general formula (W), and
Y represents a divalent group represented by chemical formula (Y1), (Y2), (Y3), (Y4), (Y5), or (Y6), and
in general formula (W),
t represents an integer of at least 1 and no greater than 3, and
asterisks each represent a bond
5. The image forming apparatus according to claim 1 , wherein
the binder resin includes a polyarylate resin having a main chain represented by general formula (20-1) and a terminal group represented by chemical formula (Z),
where in general formula (20-1), a sum of u and v is 100, and
u is a number greater than or equal to 30 and less than or equal to 70, and
in chemical formula (Z), an asterisk represents a bond.
6. The image forming apparatus according to claim 1 , wherein
the electron transport material includes both a compound represented by general formula (31) and a compound represented by general formula (32),
where in general formulae (31) and (32),
R 1 to R 4 each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 8, and
R 5 to R 8 each represent, independently of one another, a hydrogen atom, a halogen atom, or an alkyl group having a carbon number of at least 1 and no greater than 4.
7. The image forming apparatus according to claim 1 , wherein
the electron transport material includes both a compound represented by chemical formula (ETM-1) and a compound represented by chemical formula (ETM-3)
8. The image forming apparatus according to claim 1 , wherein
the single-layer photosensitive layer further contains a compound represented by general formula (40), and
the compound represented by general formula (40) is contained in an amount of greater than 0.0% by mass and no greater than 1.0% by mass relative to mass of the single-layer photosensitive layer,
R 40 -A-R 41 (40)
where in general formula (40),
R 40 and R 41 each represent, independently of one another, a hydrogen atom or a monovalent group represented by general formula (40a), and
A represents a divalent group represented by chemical formula (A1), (A2), (A3), (A4), (A5), or (A6), and
in general formula (40a), X represents a halogen atom
9. The image forming apparatus according to claim 8 , wherein
the compound represented by general formula (40) is a compound represented by chemical formula (40-1)
10. The image forming apparatus according to claim 1 , wherein
the charge generating material is contained in an amount of greater than 0.0% by mass and no greater than 1.0% by mass relative to mass of the single-layer photosensitive layer.
11. The image forming apparatus according to claim 1 , further comprising
a transfer device configured to transfer a toner image formed on the circumferential surface of the image bearing member to a transfer target, the toner image including the toner, wherein
a transfer current of the transfer device is at least −20 μA and no greater than −10 μA.
12. The image forming apparatus according to claim 1 , wherein
the charger is located in contact with or adjacent to the circumferential surface of the image bearing member.
13. The image forming apparatus according to claim 12 , wherein
a distance between the charger and the circumferential surface of the image bearing member is no greater than 50 μm.
14. A method for forming an image, comprising:
charging a circumferential surface of an image bearing member to a positive polarity; and
collecting a toner remaining on the circumferential surface of the image bearing member through a cleaning member being pressed against the circumferential surface of the image bearing member, wherein
a linear pressure N of the cleaning member on the circumferential surface of the image bearing member is at least 14 N/m and no greater than 40 N/m,
a rebound resilience R of the cleaning member at a temperature of 25° C. is at least 38%,
the leaner pressure N and the rebound resilience R satisfy mathematical formula (1A),
the image bearing member includes a conductive substrate and a single-layer photosensitive layer,
the single-layer photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin, and
the image bearing member satisfies mathematical formula (1B),
R
<
13.771
×
N
0.4043
(
1
A
)
0.60
≦
V
(
Q
/
S
)
×
(
d
/
ɛ
r
·
ɛ
0
)
(
1
B
)
where in mathematical formula (1B),
Q represents a charge amount of the image bearing member,
S represents a charge area of the image bearing member,
d represents a film thickness of the single-layer photosensitive layer,
ε r represents a specific permittivity of the binder resin contained in the single-layer photosensitive layer,
ε 0 represents a vacuum permittivity,
V is a value calculated in accordance with the following expression: V=V 0 −V r ,
V r represents a first potential of the circumferential surface of the image bearing member yet to be charged by the charger, and
V 0 represents a second potential of the circumferential surface of the image bearing member charged by the charger.Join the waitlist — get patent alerts
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